Radiobiological and dosimetric impact of RayStation pencil beam and Monte Carlo algorithms on intensity-modulated proton therapy breast cancer plans.

PURPOSE: RayStation treatment planning system employs pencil beam (PB) and Monte Carlo (MC) algorithms for proton dose calculations. The purpose of this study is to evaluate the radiobiological and dosimetric impact of RayStation PB and MC algorithms on the intensity-modulated proton therapy (IMPT) breast plans. METHODS: The current study included ten breast cancer patients, and each patient was treated with 1-2 proton beams to the whole breast/chestwall (CW) and regional lymph nodes in 28 fractions for a total dose of 50.4 Gy relative biological effectiveness (RBE). A total clinical target volume (CTV_Total) was generated by combining individual CTVs: AxI, AxII, AxIII, CW, IMN, and SCVN. All beams in the study were treated with a range shifter (7.5 cm water equivalent thickness). For each patient, three sets of plans were generated: (a) PB optimization followed by PB dose calculation (PB-PB), (b) PB optimization followed by MC dose calculation (PB-MC), and (c) MC optimization followed by MC dose calculation (MC-MC). For a given patient, each plan was robustly optimized on the CTVs with same parameters and objectives. Treatment plans were evaluated using dosimetric and radiobiological indices (equivalent uniform dose (EUD), tumor control probability (TCP), and normal tissue complication probability (NTCP)). RESULTS: The results are averaged over ten breast cancer patients. In comparison to PB-PB plans, PB-MC plans showed a reduction in CTV target dose by 5.3% for D99% and 4.1% for D95% , as well as a reduction in TCP by 1.5-2.1%. Similarly, PB overestimated the EUD of target volumes by 1.8─3.2 Gy(RBE). In contrast, MC-MC plans achieved similar dosimetric and radiobiological (EUD and TCP) results as the ones in PB-PB plans. A selection of one dose calculation algorithm over another did not produce any noticeable differences in the NTCP of the heart, lung, and skin. CONCLUSION: If MC is more accurate than PB as reported in the literature, dosimetric and radiobiological results from the current study suggest that PB overestimates the target dose, EUD, and TCP for IMPT breast cancer treatment. The overestimation of dosimetric and radiobiological results of the target volume by PB needs to be further interpreted in terms of clinical outcome.

Cost-Effectiveness of Web-Based Patient-Reported Outcome Surveillance in Patients With Lung Cancer.

INTRODUCTION: A multicenter randomized clinical trial in France found an overall survival benefit of web-based patient-reported outcome (PRO)-based surveillance after initial treatment for lung cancer compared with conventional surveillance. The aim of this study was to assess the cost-effectiveness of this PRO-based surveillance in lung cancer patients. METHODS: This medico-economic analysis used data from the clinical trial, augmented by abstracted chart data and costs of consultations, imaging, transportations, information technology, and treatments. Costs were calculated based on actual reimbursement rates in France, and health utilities were estimated based on scientific literature review. Willingness-to-pay thresholds of €30,000 per quality-adjusted life year (QALY) and €90,000 per QALY were used to define a very cost-effective and cost-effective strategy, respectively. Average annual costs of experimental and control surveillance approaches were calculated. The incremental cost-effectiveness ratio was expressed as cost per life-year gained and QALY gained, from the health insurance payer perspective. One-way and multivariate probabilistic sensitivity analyses were performed. RESULTS: Average annual cost of surveillance follow-up was €362 lower per patient in the PRO arm (€941/year/patient) compared to control (€1,304/year/patient). The PRO approach presented an incremental cost-effectiveness ratio of €12,127 per life-year gained and €20,912 per QALY gained. The probabilities that the experimental strategy is very cost-effective and cost-effective were 97% and 100%, respectively. CONCLUSIONS: Surveillance of lung cancer patients using web-based PRO reduced the follow-up costs. Compared to conventional monitoring, this surveillance modality represents a cost-effective strategy and should be considered in cancer care delivery.

Cost-Effectiveness Analysis of Afatinib versus Gefitinib for First-Line Treatment of Advanced EGFR-Mutated Advanced Non-Small Cell Lung Cancers.

INTRODUCTION: The irreversible ErbB family blocker afatinib and the reversible EGFR tyrosine kinase inhibitor gefitinib were compared in the multicenter, international, randomized, head-to-head phase 2b LUX-Lung 7 trial for first-line treatment of advanced EGFR mutation-positive NSCLCs. Afatinib and gefitinib costs and patients' outcomes in France were assessed. METHODS: A partitioned survival model was designed to assess the cost-effectiveness of afatinib versus gefitinib for EGFR mutation-positive NSCLCs. Outcomes and safety were taken primarily from the LUX-Lung 7 trial. Resource use and utilities were derived from that trial, an expert-panel questionnaire, and published literature, limiting expenditures to direct costs. Incremental cost-effectiveness ratios (ICERs) were calculated over a 10-year time horizon for the entire population, and EGFR exon 19 deletion or exon 21 L858R mutation (L858R) subgroups. Deterministic and probabilistic sensitivity analyses were conducted. RESULTS: For all EGFR mutation-positive NSCLCs, the afatinib-versus-gefitinib ICER of was €45,211 per quality-adjusted life-year (QALY) (0.170 QALY gain for an incremental cost of €7697). ICERs for EGFR exon 19 deletion and L858R populations were €38,970 and €52,518, respectively. Afatinib had 100% probability to be cost-effective at a willingness-to-pay threshold of €70,000/QALY for patients with common EGFR mutations. CONCLUSION: First-line afatinib appears cost-effective compared with gefitinib for patients with EGFR mutation-positive NSCLCs.

Dynamic evaluation of circulating tumour cells in patients with advanced gastric and oesogastric junction adenocarcinoma: Prognostic value and early assessment of therapeutic effects.

BACKGROUND: The identification of dynamic biomarkers in advanced gastric and oesogastric junction adenocarcinoma (GOA) could help to tailor strategies for each patient. Enumeration of circulating tumour cells (CTCs) is approved by the US Food and Drug Administration in breast, colon and prostate cancer but is not in advanced GOA. Our study aims to establish the optimal threshold and the clinical significance of CTC count in advanced GOA before and during treatment. METHODS: One hundred six patients with untreated advanced GOA were included in the ancillary study of the PRODIGE 17-ACCORD 20 trial. CTCs were detected in the peripheral blood using the CellSearch system on day 0 (D0) and day 28 (D28). The prognostic value of CTCs at D0 and D28 was analysed by testing several thresholds. RESULTS: At baseline, median CTC count was 1 (range, 0-415). While CTCs ≥1, 2 or 3 at D0 were all significantly associated with worse overall survival (OS) and progression-free survival (PFS), CTCs ≥2 were the optimal threshold, on D0 or D28. CTCs ≥2 at D28 were also predictive of disease control. Taking into account both D0 and D28 CTC count defined 3 groups (low/low, high/low and low-high/high) with significantly different PFS (p = 0.0002) and OS (p = 0.003). CONCLUSION: Quantification of CTCs at baseline and during treatment may be a useful prognostic tool in advanced GOA, as it is associated with worse PFS and OS. A threshold ≥2 CTCs seems to have the best discriminant value. Change in CTC count between baseline and D28 could help to tailor treatment to each individual patient.

Prevention of 5-fluorouracil-induced early severe toxicity by pre-therapeutic dihydropyrimidine dehydrogenase deficiency screening: Assessment of a multiparametric approach.

5-Fluorouracil (5-FU)-based treatments can lead to early-onset severe (4%-5%) even fatal (0.3%) toxicities in patients with dihydropyrimidine dehydrogenase (DPD) deficiency. This multicenter prospective cohort study aimed to assess the clinical benefit of pretherapeutic screening for DPD deficiency using a multiparametric approach. Two parallel cohorts of patients treated with 5-FU-based chemotherapy for colorectal carcinoma were compared in a prospective nonrandomized study. In arm A, patients had DPD deficiency screening before treatment, whereas in arm B no pretherapy screening was performed. Dosing was based on 5-FU administration guidelines of each institution. DPD deficiency screening was performed using a combined multiparametric approach (5-FUODPM Tox). The frequency of early grade 4-5 toxic events potentially induced by 5-FU was compared in the two groups. At total of 1,142 patients (n = 1,116 evaluable) were enrolled. In arm A, out of 718 evaluable patients, nine grade 4 early toxicities potentially related to 5-FU were reported in nine patients (1.2%) with no toxic death despite one complete DPD deficiency and 24 partial deficiencies. The 24 patients with partial deficiency had safe pharmacokinetics (PK)-monitored 5-FU. In arm B, among 398 evaluable patients, 17 grade 4-5 toxic early events potentially related to 5-FU were reported in 12 patients (4.2%). The incidence of early severe toxicity was significantly higher in arm B (P = .0019), confirming the positive impact of pretherapeutic DPD assessment. The percent of patients with a toxicity grade 3 or higher observed in arm A was 10.8% (n = 78) compared to 17.55% (n = 69)  in arm B (P = .0497). The percentage of death was reduced from 2.5/1,000 in arm B to 0 in arm A. The time to occurrence of all grade ≥3 toxicities was determined in both arms and the difference between the two arms was significant (P = .047). Overall, one patient with complete DPD deficiency confirmed retrospectively died within 13 days from grade 5 multivisceral toxicity. Enrollment was prematurely closed after external experts' decision. In conclusion, multiparametric pretherapeutic DPD deficiency screening significantly lowered the risk of early severe toxicity and avoided an early toxic death. This approach should be used for safe administration of 5-FU-based treatments.

Oral vinorelbine plus cisplatin versus pemetrexed plus cisplatin as first-line treatment of advanced non-squamous non-small-cell lung cancer: cost minimization analysis in 12 European countries.

OBJECTIVE: A combination of vinorelbine and cisplatin is a standard treatment in non-small-cell lung cancer; oral vinorelbine is registered in 45 countries. Pemetrexed and cisplatin are recommended in front-line chemotherapy of non-squamous non-small-cell lung cancer (NS-NSCLC). The objective of this study was to conduct a cost minimization analysis from the perspective of the national health service (NHS) in each of 12 European countries, based on a randomized phase II study in NS-NSCLC (NAVoTRIAL01), with 100 oral vinorelbine plus cisplatin patients (arm A) and 51 pemetrexed plus cisplatin patients (arm B). RESEARCH DESIGN AND METHODS: Country-specific costs and DRG codes considered included those relating to anticancer drugs, administration settings (out-patient/in-patient/at home), serious adverse events (defined as involving hospitalization and considered due to anticancer drugs) and concomitant medications. Relevant costs were calculated based on country-specific reimbursement procedures and official tariffs. MAIN OUTCOME MEASURES: Cost and savings per patient. RESULTS: Using the NHS perspective, savings per patient treated with oral vinorelbine ranged from €1317 (Denmark) to €35,001 (Germany). Expressed as percentages, savings per patient treated with oral vinorelbine compared with pemetrexed ranged between 5% (France) and 83% (Czech Republic). Pooled average costs for each treatment arm across the 12 countries resulted in cost savings for payers of €12,871, favoring oral vinorelbine plus cisplatin. CONCLUSIONS: Given the reported efficacy with both regimens, this pan-European economic analysis provides compelling evidence supporting oral vinorelbine use over pemetrexed for the treatment of NS-NSCLC. Oral vinorelbine provides similar efficacy and an easily manageable safety profile at lower overall cost per patient treated, combined with an easier/more convenient mode of administration. Sensitivity analysis across varied scenarios demonstrated the robustness of the results. The principle weakness of our study was its reliance upon a single small scale study to provide efficacy data, since this is the only study conducted in this specific population of patients. Further large scale trials are needed to confirm these results.